From:   Jens Axboe <axboe@kernel.dk>
To:     jack@suse.cz, shinichiro.kawasaki@wdc.com,
        paolo.valente@linaro.org, glusvardi@posteo.net,
        damien.lemoal@opensource.wdc.com, felicigb@gmail.com,
        inbox@emilianomaccaferri.com, Yu Kuai <yukuai1@huaweicloud.com>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com
In-Reply-To: <20230308023208.379465-1-yukuai1@huaweicloud.com>
References: <4e6e1606-1d9e-9903-8a44-ccac58a1fe06@kernel.dk>
 <20230308023208.379465-1-yukuai1@huaweicloud.com>
Subject: Re: [PATCH] block, bfq: fix uaf for 'stable_merge_bfqq'
Message-Id: <167828613700.180504.7849236814026719917.b4-ty@kernel.dk>
Date:   Wed, 08 Mar 2023 07:35:37 -0700
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On Wed, 08 Mar 2023 10:32:08 +0800, Yu Kuai wrote:
> Before commit fd571df0ac5b ("block, bfq: turn bfqq_data into an array
> in bfq_io_cq"), process reference is read before bfq_put_stable_ref(),
> and it's safe if bfq_put_stable_ref() put the last reference, because
> process reference will be 0 and 'stable_merge_bfqq' won't be accessed
> in this case. However, the commit changed the order and  will cause
> uaf for 'stable_merge_bfqq'.
> 
> [...]

Applied, thanks!

[1/1] block, bfq: fix uaf for 'stable_merge_bfqq'
      commit: e2f2a39452c43b64ea3191642a2661cb8d03827a

Best regards,
-- 
Jens Axboe